1. Field of the Invention
The present invention provides azeotrope-like compositions of 1,1,1,2,2-pentafluoropropane (HFC-245cb) with either the Z isomer of 1,1,1,2,3-pentafluoropropene (HFO-1225ye(Z)) or with a mixture of the E and Z isomers of 1,1,1,2,3-pentafluoropropene (HFO-1225 ye(Z) and HFO-1225 ye(E)); and uses thereof, and in process for separating the azeotrope-like mixtures.
2. Description of the Related Art
Fluorocarbon based fluids have found widespread use in industry in a number of applications, including as refrigerants, aerosol propellants, blowing agents, heat transfer media, and gaseous dielectrics. Because of the suspected environmental problems associated with the use of some of these fluids, including the relatively high global warming potentials associated therewith, it is desirable to use fluids having low or even zero ozone depletion potential. Thus, the use of fluids that do not contain chlorofluorocarbons (“CFCs”) or hydrochlorofluorocarbons (“HCFCs”) is desirable. Compounds having a low ozone depletion potential include hydrofluorocarbons (“HFCs”), especially hydrofluoroolefins (“HFO's”). Compounds having a low global warming potential are also desirable. In this regard, the use of alkenes is also desirable due to their short atmospheric lifetime which results in a relatively low global warming potential. Additionally, the use of single component fluids or azeotropic mixtures, which do not fractionate on boiling and evaporation, is desirable. However, the identification of new, environmentally safe, non-fractionating mixtures is complicated due to the fact that azeotrope formation is not readily predictable.
The industry is continually seeking new fluorocarbon based mixtures that offer alternatives, and are considered environmentally safer substitutes for CFCs and HCFCs. Of particular interest are mixtures containing hydrofluorocarbons, fluoroolefins and other fluorinated compounds, which have a low ozone depletion potentials and low global warming potential. Such mixtures are the subject of this invention.
U.S. Pat. No. 7,161,049 shows a process for purifying hydrofluoropropanes which may include HFC-235cb or HFO-1225ye, however, no azeotrope-like compositions thereof are disclosed. U.S. Pat. No. 7,077,960 discloses a process for the production of a hydrofluoroalkane, according to which hydrofluoroalkane comprising organic impurities is subjected to at least two distillations. Again, no azeotrope-like compositions thereof are disclosed. This invention concerns compositions that help to satisfy the continuing need for alternatives to CFCs and HCFCs. The compositions of the invention exhibit relatively low global warming potentials (“GWP”). Accordingly, it has been recognized that such compositions can be used to great advantage in a number of applications, including as replacements for CFCs, HCFC's, and HFCs such as HFC-134a in refrigerant, aerosol, blowing agents, and other applications. This is accomplished by azeotrope-like compositions of HFC-245cb with either the Z isomer of HFO-1225ye(Z) or with mixtures of the E and Z isomers HFO-1225 ye(Z) and HFO-1225 ye(E).